Last week, my 10yo son and I started exploring strategies to help with multi-digit addition fluency. The "Give and Take"* strategy has given us inspiration and taken away some of our math anxiety. Here's how it works...
Let's say you're asked to add two, somewhat unfriendly, numbers.
97 + 78
Yuck. Not a great combination.
But what if you could do a little give-and-take to make it easier?
97 + 78 = 97 + (3 + 75) = (97 + 3) + 75 = 100 + 75 = 175
Which would you rather solve?
97 + 78
-OR-
100 + 75
The consensus was pretty clear around here!
How about:
443 + 289
What if we "take" 11 from 443 (443 - 11 = 432) and "give" it to 289 (289 + 11 = 300)? Is it easier to now add 432 + 300?
My 10yo explains the strategy in his math journal, in the photos you see here.
So "witch" would you rather add? :)
After journaling, to solidify the concept, he made up his own problem:
270 + 665
He took/gave 30:
300 + 635 = 935
And today, he applied it to a story problem where he had to add 275 + 168. He took/gave 25 to end up with 300 + 143. He bubbled with excitement ("MOM!!!!!"), telling me how great the give/take strategy works!
I hope this gives you a little inspiration to take back to class!
P.S. This also works well with decimals!
*The Bridges Curriculum calls this the "Give and Take" strategy.
0 Response to "Give (and Take!) Me a Great Addition Strategy"
Post a Comment